PREVIOUS TO THE LAST GEOLOGICAL REVOLUTION. 253 



correct (at which we should not be surprised, when we 

 remember that other animals, more likely to attract man's 

 attention, such as the tapir and the bear, had escaped the 

 observation of naturalists, in those very same mountains, 

 until a very recent period), we are then brought back to 

 this remarkable result, that two genera, which are at present 

 restricted to the highest chain of the South American coast, 

 were in the age of our fossil remains extended over its plains. 

 The discovery of an animal form, now usually considered 

 as peculiar to the old world, among the purely American 

 forms such as the extinct fauna of this quarter has hitherto 

 produced, being a fact of great importance, I thought it 

 right to allude to this novel information, while I reserve my- 

 self from giving any positive judgment, until farther en- 

 quiries shall have enabled M. Gay to verify or disprove this 

 report. 



But not only the number of genera, but also the total 

 amount of species, was greater in those days, than now. 

 There are now iive species (all as before mentioned belonging 

 to the genus Cervus) that inhabit this district : while 1 al- 

 ready reckon seven species of the four fossil genera. The 

 great number of species which the genus Cervus now con- 

 tains within this region, inclines us to suspect that our know- 

 ledge of the fossil species is very far from being complete. 

 The circumstance of these animals living solitary, or at most 

 in small herds, together with their rapidity of flight, secures 

 them from the attacks of predatory beasts, much more than 

 animals that either live in large societies, like the cloven- 

 footed, or which are bad runners, as the Tardigrada ; and this 

 accounts for our finding their remains so seldom in the caves 

 of wild beasts, in comparison with those of the other classes. 

 Therefore, as the main result of our enquiry respecting this 

 family, we see that of the four genera of which it was com- 

 posed in that former period, only one still continues to exist 

 in this same district ; two must be sought for in the higher 

 chain of the Andes (or perhaps only in the warmer zones of 

 the Old World), and finally, one has entirely disappeared 

 from the surface of the earth. 



Second Family, Pachydermata. 



This family at present contains only two genera belonging 

 to Brazil ; the tapir, with one species, and the peccari (Dico- 

 tyles) with two. I am in possession of fossil bones, which evi- 

 dently belong to the first genus ; but they are too imperfect 

 t ) determine their relation to the recent animal. 



